Among the adenomatous polyps 29 cases were tubular adenomas, 12 cases were tubulovillous adenomas and 6 cases were villous adenomas
. So, majority of polyps were tubular adenomas.
One hundred twenty one (29.8%) patients had hyperplastic polyps, 331 (81.7%) patients had tubular adenomas, 33 (8.1%) patients had tubulovillous adenomas, 12 (2.9%) patients had villous adenomas
, 13 (3.2%) patients had serrated adenomas and 61 (15.0%) patients had adenocarcinoma (Figure 1).
There are no specific imaging findings on CT scan for villous adenoma
of the renal pelvis.
In addition, the appearance and degree of cytologic atypia in MCTLMP often resembles that seen in villous adenomas
of the lower gastrointestinal tract (or urinary bladder; see below), including nuclear elongation and pseudostratification (Figure 1, D), and for this reason, MCTLMP may pose a diagnostic challenge for a variety of well-differentiated glandular tumors of the urachus and urinary bladder (see below).
studied 893 cases of colorectal carcinomas, out of which mucinous carcinoma comprised 132 cases and noted that 31% of mucinous carcinomas were associated with villous adenomas
, implying a histogenetic relationship.
Fifty-four lesions (23 with atypia) were found: 35 tubular adenomas, 7 villous adenomas
, 11 tubular villous adenomas
, and one adenocarcinoma.
(6,9) The coexistence of villous adenoma
with adenocarcinoma, squamous cell carcinoma, and urothelial carcinoma has been documented, necessitating thorough sampling of any lesion diagnosed by biopsy as villous adenoma
(a) Includes sessile serrated adenoma, villous adenoma
, tubulovillous adenoma, and tubular adenoma.
Although very rarely villous adenomas
extend into the cecum from the appendix, (11) this unlikely possibility can be excluded with colonoscopic examination, as has been suggested by others.
(53,54) However, CIMP+ carcinomas do not arise from conventional adenomas, such as tubular adenoma, tubulo-villous adenoma, and villous adenoma
, but instead develop from sessile or traditional serrated adenomas.
(11) We felt that because appendiceal tumors that are confined to the appendix (ergo, mucinous cystadenoma or villous adenoma
) are indistinguishable from those that have spread to the peritoneum, a single term should be used to encompass low-grade appendiceal mucinous tumors, regardless of their stage.
Preexisting Villous Adenoma
in Colorectal Adenocarcinoma Predicts the Status of KRAS Mutation in Targeted Therapy.